Gas exchange at whole plant level shows that a less conservative water use is linked to a higher performance in three ecologically distinct pine species

Increasing temperatures and decreasing precipitation in large areas of the planet as a consequence of global warming will affect plant growth and survival. However, the impact of climatic conditions will differ across species depending on their stomatal response to increasing aridity, as this will ultimately affect the balance between carbon assimilation and water loss. In this study, we monitored gas exchange, growth and survival in saplings of three widely distributed European pine species (Pinus halepensis, P. nigra and P. sylvestris) with contrasting distribution and ecological requirements in order to ascertain the relationship between stomatal control and plant performance. The experiment was conducted in a common garden environment resembling rainfall and temperature conditions that two of the three species are expected to encounter in the near future. In addition, gas exchange was monitored both at the leaf and at the whole-plant level using a transient-state closed chamber, which allowed us to model the response of the whole plant to increased air evaporative demand (AED). P. sylvestris was the species with lowest survival and performance. By contrast, P. halepensis showed no mortality, much higher growth (two orders of magnitude), carbon assimilation (ca. 14 fold higher) and stomatal conductance and water transpiration (ca. 4 fold higher) than the other two species. As a consequence, P. halepensis exhibited higher values of water-use efficiency than the rest of the species even at the highest values of AED. Overall, the results strongly support that the weaker stomatal control of P. halepensis, which is linked to lower stem water potential, enabled this species to maximize carbon uptake under drought stress and ultimately outperform the more water conservative P. nigra and P. sylvestris. These results suggest that under a hotter drought scenario P. nigra and P. sylvestris would very likely suffer increased mortality, whereas P. halepensis could maintain gas exchange and avoid water-induced growth limitation. This might ultimately foster an expansion of P. halepensis to higher latitudes and elevations.This work was supported by the projects ECOLPIN (AGL2011–24296) and Remedinal 3 (S2013/ MAE- 2719) of the Madrid Government, by a FPU fellowship from the Spanish Ministry of Education, Culture and Sport (FPU13/03410) to DS and by EU Marie Curie (FP7–2013-IOF-625988) fellowship to EPSC

Assessment, design, and preparation of lime-based mortars reinforced with Ca(OH)2 and SiO2 nanoparticles for cultural heritage

Trabajo presentado en Green Conservation of Cultural Heritage - 2nd International Conference, celebrada en Palermo (Italia) del 16 al 18 de noviembre de 2017Peer reviewe

Assessment on the performances of air lime-ceramic mortars with nano-Ca(OH)2 and nano-SiO2 additions

This research presents a novel approach based on the combination of nanotechnology and Roman technology by investigating how adding nanoCa(OH) and nanoSiO modify the performance of air lime mortars containing Roman ceramics. Microstructural, physico-mechanical properties were periodically controlled until 120 days of curing. XRD and TGA analyses showed that adding nanoSiO either alone or with nanoCa(OH) were more beneficial to improve the pozzolanic activity in the mortars. The less stable hydrated phases generated led to microcracks which eventually impaired compressive strength but enhanced deformability capacity. These results provide insight into the development of highly compatible mortars for cultural heritage

Las nonocales: un gran avance en conservación y restauración del patrimonio pétreo

Trabajo presentado en las VI Jornadas FICAL (Fórum Ibérico de la Cal), celebradas en Pamplona (España), del 28 al 30 de mayo de 2018Con el desarrollo de la nanotecnología, se abrió un amplio panorama en diversos campos de la investigación y sus aplicaciones. Dentro de ellos, existe una gran oportunidad en la utilización de nanocales para la conservación y restauración del patrimonio. En este contexto, su aplicación se ha incrementado notoriamente en los últimos años, pudiéndose mencionar su uso como material consolidante y aditivo para morteros. Sin embargo, existen numerosos factores que afectan su estabilidad, que deben tenerse en cuenta en tratamientos de conservación. Dentro de las posibles variaciones, factores como la morfología, el tamaño de partícula, el tipo de solvente, la concentración o el método de aplicación, resultan fundamentales para obtener un alto grado de efectividad. Igualmente, las nanocales son altamente susceptibles a las condiciones ambientales, incluyendo las fluctuaciones de la humedad relativa o la temperatura, así como el tiempo de exposición, siendo criterios importantes a la hora de estudiar su efectividad. El presente trabajo incluye un estudio comparativo de la estabilidad de diferentes tipos de nanocales, para su utilización en materiales de construcción (morteros, piedra caliza y dolomía). Se analizan no solamente los aciertos sino los errores más comunes que pueden llegar a producirse con el uso inadecuado de las nanocales.El trabajo está financiado por los proyectos GEOMATERIALES 2 (S2013/MIT_2914) y CLIMORTEC (BIA2014-53911-R) del Ministerio de Economía.Peer reviewe